Maintaining quality assurance for sonographic nuchal translucency measurement: lessons from the FASTER Trial.

OBJECTIVE: To evaluate nuchal translucency measurement quality assurance techniques in a large-scale study. METHODS: From 1999 to 2001, unselected patients with singleton gestations between 10 + 3 weeks and 13 + 6 weeks were recruited from 15 centers. Sonographic nuchal translucency measurement was performed by trained technicians. Four levels of quality assurance were employed: (1) a standardized protocol utilized by each sonographer; (2) local-image review by a second sonographer; (3) central-image scoring by a single physician; and (4) epidemiological monitoring of all accepted nuchal translucency measurements cross-sectionally and over time. RESULTS: Detailed quality assessment was available for 37 018 patients. Nuchal translucency measurement was successful in 96.3% of women. Local reviewers rejected 0.8% of images, and the single central physician reviewer rejected a further 2.9%. Multivariate analysis indicated that higher body mass index, earlier gestational age and transvaginal probe use were predictors of failure of nuchal translucency measurement and central image rejection (P = 0.001). Epidemiological monitoring identified a drift in measurements over time. CONCLUSION: Despite initial training and continuous image review, changes in nuchal translucency measurements occur over time. To maintain screening accuracy, ongoing quality assessment is needed.

First- and second-trimester Down syndrome screening markers in pregnancies achieved through assisted reproductive technologies (ART): a FASTER trial study.

OBJECTIVE: To determine whether first- and second-trimester Down syndrome screening markers and screen-positive rates are altered in pregnancies conceived using assisted reproductive technologies (ARTs). METHODS: ART pregnancies in the multicenter FASTER trial were identified. Marker levels were evaluated for five types of ART: in vitro fertilization with ovulation induction (IVF-OI), IVF with OI and egg donation (IVF-OI-ED), IVF with ED (IVF-ED), and intrauterine insemination with OI (IUI-OI) or without OI (IUI). Each group was compared to non-ART controls using Mann-Whitney U analysis. RESULTS: First-trimester marker levels were not significantly different between ART and control pregnancies, with the exception of reduced PAPP-A levels in the IUI-OI group. In contrast, second-trimester inhibin A levels were increased in all ART pregnancies, estriol was reduced and human chorionic gonadotropin (hCG) was increased in IVF and IUI pregnancies without ED, and alpha-fetoprotein (AFP) was increased in ED pregnancies. Second-trimester screen-positive rates were significantly higher than expected for ART pregnancies, except when ED was used. CONCLUSIONS: These data show that ART significantly impacts second-, but not first-, trimester markers and screen-positive rates. The type of adjustment needed in second-trimester screening depends on the particular type of ART used.

Human fetal and neonatal movement patterns: Gender differences and fetal-to-neonatal continuity.

Longitudinal quantification of leg movements per minute for human subjects during both fetal and neonatal periods was accomplished from videotapings conducted antenatally (ultrasonography 30, 34, and 37 weeks gestational age) and postnatally (birth and 6 weeks of age). Fetal/neonatal subjects displayed decreasing numbers of leg movements per minute during antenatal development (30 to 37 weeks), followed by increasing numbers of leg movements per minute during postnatal development (birth to 6 weeks of age). Male subjects displayed greater numbers of leg movements per minute than female subjects during both antenatal and postnatal development. Fetal-to-neonatal continuity for numbers of leg movements per minute was found for comparisons between fetal (37 weeks gestational age) and neonatal (during sleep states at birth) measures, and females displayed a stronger and different movement continuity pattern than males. These results indicate a differential time course for neurobehavioral development of male and female fetuses/neonates, and the findings have implications for the clinical assessment of fetal neurobehavioral development and well-being.

Prevalence of aneuploidy and additional anatomic abnormalities in fetuses and neonates with cleft lip with or without cleft palate: a population-based study in Utah.

OBJECTIVE: To determine the prevalence of aneuploidy and additional major anatomic abnormalities in fetuses and neonates with cleft lip with or without cleft palate. METHODS: All cases of cleft lip with or without cleft palate (cleft lip/cleft palate) occurring in Utah from 1995 through 1999 were reviewed by using the Utah Birth Defect Network population-based surveillance system. All pregnancy outcomes are included (stillborn, live born, and termination) in this analysis. RESULTS: Of 263 cases of cleft lip/cleft palate, 72 (27.4%) were unilateral cleft lip, 112 (42.6%) were unilateral cleft lip and cleft palate, 12 (4.6%) were bilateral cleft lip, and 67 (25.5%) were bilateral cleft lip and cleft palate. Fifteen (5.7%) of the 263 fetuses and neonates were aneuploid. One (1.2%) with cleft lip (unilateral and bilateral combined) was aneuploid. Five (4.5%) of the fetuses and neonates with unilateral cleft lip and cleft palate were aneuploid compared with 9 (13.4%) of fetuses and neonates with bilateral cleft lip and cleft palate. In known or presumed euploid fetuses and neonates, additional sonographically occult major anatomic abnormalities occurred in 5 (7.0%) of 71 with unilateral cleft lip, 18 (16.8%) of 107 with unilateral cleft lip and cleft palate, 1 (8.3%) of 12 with bilateral cleft lip, and 12 (20.7%) of 58 with bilateral cleft lip and cleft palate. These abnormalities primarily involved the heart and the central nervous system. CONCLUSIONS: Amniocentesis for karyotype should be offered in all cases of cleft lip/cleft palate because of the risk of aneuploidy. Patients should be counseled that sonographically occult additional anatomic abnormalities might be present with all clefts.

Prevalence of aneuploidy and additional anatomic abnormalities in fetuses with open spina bifida: population based study in Utah.

Data were used to determine the population prevalence of aneuploidy and additional anatomic abnormalities in fetuses with open spina bifida. The ability of sonography to predict aneuploidy and identify additional anatomic abnormalities in euploid fetuses was assessed. All cases of spina bifida occurring in the state of Utah from 1995 through 1997 were reviewed using Utah Birth Defect Network data, including stillborn, liveborn, and terminated cases. Chromosomes were known in 45 of 51 cases of open spina bifida. Of the 45 fetuses, 6 (13%) were aneuploid. Major anatomic abnormalities were present in four of six (67%) cases, and two of six (33%) cases had additional anomalies that could be missed sonographically. Of 39 euploid fetuses, 12 (31%) had additional abnormalities, but only half likely would be detected sonographically. Our 4% risk of aneuploidy in sonographically isolated spina bifida is substantially higher than the risk associated with advanced maternal age (0.37%).

The sonography of pregnancy loss.

Sonography is critical to the current management of pregnancy loss. It is used to predict and/or confirm viability. Knowledge of the early embryology as well as the timing of these events is important to appropriate management. Sonographic parameters can be divided into hard and soft signs. Hard signs include the absence of visible heart motion or embryonic poles at certain cutoffs. The soft signs are generally related to findings more likely to be associated with poor outcomes. Ultrasound is now also used to help determine which patients may not require surgical intervention.

Morphologic observations in a case of lethal variant (type I) metatropic dysplasia with atypical features: morphology of lethal metatropic dysplasia.

Metatropic dysplasia accounts for approximately 5% of cases recorded by the International Skeletal Dysplasia Registry, with a single recorded lethal case. Four forms of the disease are currently recognized: type I, lethal autosomal recessive form; type II, nonlethal autosomal recessive form with survival to childhood; type III, autosomal dominant form with typical features, and type IV, a mild form with uncertain inheritance. The literature contains few well-documented reports of the histopathologic findings in metatropic dysplasia. In this report, we present the radiologic and histopathologic features in a cas e of type I metatropic dysplasia, with the unusual features of a persist ent tail, unique lung dysmorphology, and thyroidal agenesis.

Clinical significance of sonographically detected uterine synechiae in pregnant patients.

The null hypothesis for this study is that there is no difference in outcome comparing pregnancies with sonographically documented uterine synechiae to those without synechiae. A retrospective case-control study was performed to test this hypothesis. The cases and controls were part of a population of 29,543 patients who underwent ultrasonographic examination at our institution between March 1988 and March 1995. The cases of synechiae were determined by the sonographic finding of a shelflike protrusion into the amniotic cavity. Each case was matched to controls. Matching criteria were maternal age, gestational age at scan, and type of invasive procedure if applicable. Outcome data were obtained by review of medical records and patient and physician interviews. Statistical analysis was performed using the chi-square analysis with Yates correction. Odds ratios were calculated. The overall prevalence of uterine synechiae was 0.47% (140 of 29,543) in the scanned population. No significant difference was found between cases and controls with respect to maternal age, reproductive losses, and medical problems. The mean gestational age at time of diagnosis was 18.3 +/- 4.2 weeks. No difference in outcome existed between cases and controls except for mean birth weight. We conclude that the presence of uterine synechiae does not appear to confer an increased risk for poor pregnancy outcome or for malpresentation.

The clinical significance of ultransonographically detected subchorionic hemorrhages.

OBJECTIVES: The null hypothesis is that there is no difference in outcome when pregnancies with ultrasonographically documented subchorionic hemorrhages are compared with those without these hemorrhages. STUDY DESIGN: We performed a case-control study, utilizing our computerized ultrasonographic database. Cases were matched with two or three controls in two separate control groups. Matching criteria were maternal age, gestational age at scan, and invasive procedures (chorionic villus sampling or amniocentesis). General exclusion criteria were absence of fetal heart motion and fetal anomalies. Presence of subchorionic hemorrhage was an exclusion criterion for both control groups; however, in addition, presence of vaginal bleeding was a further criterion for one of the two. Statistical analysis was performed with chi2 analysis and Yates' correction. Odd ratios and 95% confidence intervals were calculated. RESULTS: There was no difference in maternal characteristics between the cases and controls. The incidence of subchorionic hemorrhage was 1.3%. There was an increased risk of miscarriage (odds ratio 2.8, 95% confidence interval 1.7 to 7.4), stillbirth (4.5, 1.5 to 13.2), abruptio placentae (11.2, 2.7 to 46.4), and preterm labor (2.6, 1.5 to 4.6) when cases were compared with controls without subchorionic hemorrhage or bleeding. These risks were also increased in comparison with the control group with bleeding, except with respect to miscarriage. In this case the risks were similar in both cases and controls but increased with respect to the controls without bleeding. The mean birth weight was lower in the cases than in both control groups. CONCLUSION: The presence of an ultransonographically detected subchorionic hemorrhage increases the risk of miscarriage, stillbirth, abruptio placentae, and preterm labor. The presence of bleeding alone appears to increase the risk of miscarriage. It is unclear whether the subchorionic hemorrhage is causative or whether it is simply a sign of an underlying process that produces these negative effects.

Spontaneous uterine rupture and hemoperitoneum in the first trimester.

Uterine rupture, a potentially catastrophic complication during pregnancy, has been reported to occur spontaneously in the second and third trimesters. We describe a case of spontaneous uterine rupture at 8 weeks' gestation in a 29-year-old woman, who has a history of systemic lupus erythematosus. The diagnosis was established with the aid of ultrasound imaging. She underwent local excision of the perforated area of the uterus. Histologic examination revealed exuberant intermediate trophoblast. On follow-up, human chorionic gonadotropin (hCG) titers returned to normal over a 15-week period. We conclude that spontaneous uterine rupture can occur in the first trimester, and early utilization of ultrasound could help in the management of this serious condition.

Regional blood flow and metabolism in ovine fetuses during severe cord occlusion.

OBJECTIVE: Our purpose was to compare the ovine fetal response to severe, damaging asphyxia resulting from umbilical cord occlusion with that seen in uterine artery occlusion. STUDY DESIGN: Six ovine fetuses were exposed to severe asphyxia produced by partial umbilical cord occlusion for 90 minutes. Fetal blood pressure and heart rate, blood gases, acid base status, electrocorticogram, and electromyogram were recorded. Regional blood flow (radioactive microspheres) measurements were performed at control and 30, 60, and 90 minutes of occlusion and 30 minutes after release. RESULTS: During the period of occlusion pH fell from 7.37 +/- 0.01 (mean +/- SEM) to 6.82 +/- 0.03 at 90 minutes, base excess from 5 +/- 1 to -22 +/- 2 mEq.L-1 and oxygen content from 3.3 +/- 0.4 mmol.L-1 to a nadir of 1.6 +/- 0.4 mmol.L-1 (p < 0.05). There was no significant long-term change in fetal heart rate or blood pressures. The fetal electrocorticogram was profoundly suppressed during asphyxia, and seizure activity was documented after release of occlusion in all surviving animals. Umbilical blood flow fell to 21% +/- 5% of control by 60 minutes of occlusion and remained depressed until release. Brain and adrenal blood flows increased during asphyxia. Heart and intestinal blood flows did not change significantly from control values. Combined ventricular output and spleen, kidney, and carcass blood flow fell during the insult. Oxygen uptake by the cerebral cortex remained stable during occlusion. Oxygen uptake by the lower carcass fell to 15% +/- 7% of control. CONCLUSION: Umbilical cord occlusion produces similar levels of asphyxia and evidence of encephalopathy (seizures), compared with previous experiments with uterine artery occlusion. The fetal response with respect to blood flow redistribution and organ oxygen uptake, however, differs. These differences may signify that with uterine artery occlusion the brain may be more vulnerable, whereas with umbilical cord occlusion the heart may be at greater risk.

Regional blood flow in asphyxiated fetuses with seizures.

OBJECTIVE: Our purpose was to determine ovine fetal regional blood flow changes during asphyxia of such severity that it results in seizures. STUDY DESIGN: Six ovine fetuses were exposed to severe asphyxia produced by maternal uterine artery occlusion for up to 90 minutes. Fetal blood pressure and heart rate, blood gases, acid base status, electrocorticogram, electromyogram and regional blood flow (radioactive microspheres) measurements were recorded. RESULTS: During the asphyxial insult pH fell from 7.39 +/- 0.01 (mean +/- SEM) to 6.99 +/- 0.01 at 60 minutes, base excess from 4 +/- 1 to -16 +/- 1 mEq/L, and oxygen content from 3.5 +/- 0.4 to 0.5 +/- 0.1 mmol/L (p < 0.05). There was no significant change in fetal heart rate or blood pressure. The fetal electrocorticogram was profoundly suppressed during asphyxia, and seizure activity began 50 +/- 19 minutes after the release of occlusion in all surviving animals. Blood flow increased to the heart and adrenals during asphyxia and decreased to spleen, gut, kidneys, and carcass (p < 0.05). There was no change in combined ventricular output and umbilical blood flow. There was no significant increase in total cerebral perfusion. CONCLUSION: When the ovine fetus is exposed to asphyxia of sufficient severity to produce neurologic damage (seizures), the pattern of redistribution of blood flow is comparable to the response to lesser asphyxia, except that a significant increase in total brain blood flow does not occur. This finding may have an important association with the development of long-term neurologic damage.

The lemon sign: not a specific indicator of meningomyelocele.

The association of the "lemon sign" with myelomeningocele has been well documented. This study was performed to determine if this sign is exclusive to myelomeningocele. The study population included all abnormal fetuses in our data base with this sonographically observed finding, from 1988 to 1991 (total of 23 cases). Twelve fetuses were found to have a myelomeningocele and six an encephalocele. Five fetuses with the lemon sign demonstrated a variety of structural anomalies not involving the neural tube. This sonographic finding appears not to be limited to cases of myelomeningocele.

Effects of propofol and thiopental on maternal and fetal cardiovascular and acid-base variables in the pregnant ewe.

BACKGROUND: The effects of propofol on uterine blood flow are not understood well. This is a relatively new agent that is finding increased use for nonobstetric surgical procedures during pregnancy and induction of anesthesia for cesarean section. METHODS: The effects of induction and maintenance of anesthesia with propofol were studied on maternal and fetal cardiovascular and acid-base variables in a chronically instrumented pregnant sheep model. Anesthesia was induced with a 2 mg/kg bolus of propofol and maintained with of one of three continuous infusions: 150, 300, and 450 micrograms.kg-1 x min-1. The control group received thiopental for induction, and anesthesia was maintained with isoflurane. RESULTS: The use of propofol did not adversely affect maternal or fetal mean arterial pressure, heart rate, or base excess, fetal heart rate variability, or uterine blood flow. Uterine blood flow transiently decreased during induction and intubation with thiopental but remained stable during induction with propofol. However, administration of succinylcholine for intubation in the presence of propofol resulted in a transient, but severe, maternal bradycardia. Continuous infusion of 300 micrograms.kg-1.min-1 of propofol appeared to provide satisfactory anesthesia in the ewe. CONCLUSIONS: Assuming the applicability of ovine data to humans, these findings suggest that induction and maintenance of anesthesia with propofol and 50% nitrous oxide in oxygen has no adverse fetal effects but warrants caution because of the potential risk of severe maternal bradycardia during induction of anesthesia using the combination of propofol and succinylcholine.

The physiologic mechanisms of variable decelerations.

OBJECTIVES: The purpose of this study was to determine the cause and physiologic consequences of variable decelerations. STUDY DESIGN: Previous studies of heart rate changes in human and experimental animals were critically reviewed with respect to the autonomic nervous system component, the cause of the increased vagal activity, and the role of cord compression or other stimuli in these heart rate changes. RESULTS: There is abundant evidence from experimental and human studies that variable decelerations can be reproduced by either cord compression or head compression. The vagal reflex produced is probably caused by a combination of chemoreflex (earlier in the deceleration) and baroreflex (later). The variable deceleration is accompanied by an acidosis, primarily respiratory, and probably hypoxemia. Cord compression results in decreased umbilical blood flow. CONCLUSIONS: Recent Doppler velocimetry studies suggest that even though the variable decelerations may be similar in duration and depth, the reduction of umbilical blood flow may be greater when the prime cause is cord compression than when the prime cause is vagal reflex from another source.

Cervical pregnancy. A case report.

A cervical pregnancy was treated successfully with systemic methotrexate and folic acid. Serial beta-human chorionic gonadotropin levels, color Doppler velocimetry and hysteroscopy were used to monitor therapy. In view of the substantial morbidity associated with this form of ectopic pregnancy, medical management is an option for treatment.